pass page title to the iframe

web/app/embed.js

@@ -58,6 +58,12 @@ function init() {
   document.addEventListener('click', postClickOutsideToIframe);
   setTimeout(postHashToIframe, 1000);
 
+  postTitleToIframe(document.title);
+  new MutationObserver(mutations => postTitleToIframe(mutations[0].target.textContent)).observe(
+    document.querySelector('title'),
+    { subtree: true, characterData: true, childList: true }
+  );
+
   const remarkRootId = 'remark-km423lmfdslkm34';
   const userInfo = {
     node: null,
@@ -242,6 +248,10 @@ function init() {
     }
   }
 
+  function postTitleToIframe(title) {
+    iframe.contentWindow.postMessage(JSON.stringify({ title }), '*');
+  }
+
   function postClickOutsideToIframe(e) {
     if (!iframe.contains(e.target)) {
       iframe.contentWindow.postMessage(JSON.stringify({ clickOutside: true }), '*');

web/iframe.html

@@ -104,6 +104,10 @@
         if (isItHash) {
           location.replace(data.hash);
         }
+
+        if (data.title) {
+          document.title = data.title;
+        }
       } catch (e) {}
     }
   </script>